When teenager Vivian Middleton goes missing her parents are frantic with worry. PC Mason discovers she had an American boyfriend called Bobby and sets out to find him. Bobby, though, says he has no idea where she could be and seems concerned. But is he hiding something
| Name | Type | Role | |
|---|---|---|---|
| Tessa Peake-Jones | Guest Star | Jocelyn Middleton | |
| Nicola Daniels | Actor | Helen | |
| Pete Dunwell | Actor | Cyril | |
| John Duttine | Actor | Sergeant George Miller | |
| Rupert Vansittart | Actor | Lord Ashfordly | |
| Adrian Lukis | Actor | Rupert Middleton | |
| Lisa Kay | Actor | Carol Cassidy | |
| William Simons | Actor | Alf Ventress | |
| Peter Benson | Actor | Bernie Scripps | |
| David Lonsdale | Actor | David Stockwell | |
| Tricia Penrose | Actor | Gina Bellamy | |
| Rupert Ward-Lewis | Actor | PC Don Wetherby | |
| Jeff Merchant | Actor | Harry Yates | |
| Gwen Taylor | Actor | Peggy Armstrong | |
| Clare Wille | Actor | DS Rachel Dawson | |
| Joe McFadden | Actor | PC Joe Mason | |
| Genevieve Gaunt | Actor | Vivienne Middleton | |
| Joe Doyle | Actor | Bobby Wilson |